n = int(input())

def main():
    ans = n
    for i in range(1,62):
        l = 0
        r = n+1
        while r-l > 1:
            mid = (r + l) // 2
            if isok(mid, i):
                l = mid
            else:
                r = mid
        ans = min(n-l ** i + l + i, ans)
    
    return print(ans)

def isok(mid, p):
    if mid ** p > n:
        return False
    else:
        return True


if __name__ == "__main__":
    main()